Protective device for gaseous fuel line

ABSTRACT

A diaphragm operated rod is mounted in a gaseous fuel line and aligned with an orifice in the line so that the rod enters and blocks the orifice when it is not in use. This prevents spiders and other insects from entering the orifice. When gaseous fluid is supplied to the line it moves the diaphragm to extract the rod from the orifice and permits fuel to be supplied to a burner at the end of the line.

United States P319111 [1 1 Eschman 1 Apr. 10, 1973 e [541 PROTECTIVE DEVICE FOR GASEOUS 695,232 3 1902 Reynolds ..137/510 x FUEL LINE 2,326,825 8/1943 Bucknan..... ...137/510.X

' 1,783,646 12/1930 Hajek, ..137/510 [75] In or: Marcel Eschman, Bellevllle. 2,135,585 11/1938 Long "137/510 x [73] Assignee: Empire Stove Company, Belleville, Prima'y Examiner flamld W weakley v Attorney-Gravely, Lieder & Woodruff [22] Filed: Mar. 4, 1971 A [21] Appl.No.: 120,831 [57] ABS CT A diaphragm operated rod is mounted in a gaseous fuel line and aligned with an orifice in the line so that [52] US. Cl. .,...431/89, 137/244, 137/510, the rod enters and blocks the orifice when it is not in 431/123 use. This prevents spiders and other insects from en- [51] Int. Cl ..-...F2 3n tering the orifice w gaseous fluid is Supplied to [58] Field of Search ..137/510, 244, h i i moves the di h to extract the rod 123 from the orifice and permits fuel to be supplied to a 1 burner at the end of the line.

[56] References Cited 8 Claims, 4 Drawing Figures UNITED STATES PATENTS 1,285,493 11/1918 Wallace ..137/5lO-X PROTECTIVE DEVICE FOR GASEOUS FUEL LINE BACKGROUND OF THE INVENTION In direct fired furnaces which have sealed combustion chambers the air for combustion is supplied directly to the burner area from outside the building being heated. This means that the interior of the burner and the combustion unit is available to and accessible from outside the building. Therefore insects, particularly spiders, attracted by the warmth of the constantly burning pilot, tend to migrate into the burner assembly. Since spiders have a tendency to enter small openings, the spiders often times enter the burner orifice in the fuel line. After entering the fuel line, the spider may grow and be unable to pass back out of the orifice. After dying, the spiders tend to block the line by being wedged in or blocking the orifice. It has been estimated that a substantial percentage, possibly 80-90 percent, of service calls on sealed combustion heating units are caused by spidersblocking the fuel line orifice. Spider blockage is also a major service problem in gas operated air conditioning units.

It has been proposed to screen the air intake, but this allows ice and snow to block the intake in cold weather and also allows the intake to be clogged by dust and the like. As the sealed combustion units are very dependent on a proper combination of air for combustion, any such interferences with the flow of combustion air into the units results in inefficient operation of the unit.

Accordingly, a principle object of the present invention is to provide a means for plugging the orifice when the burner is not in operation, but still allowing gas to pass through the orifice when the burner is in use. It is a further object of the present invention to provide a means responsive to the demand for fuel by the burner for automatically extracting a plunger from the orifice and thus opening the orifice permitting a flow of gaseous fuel to the burner.

The present invention comprises a plunger which is designed to enter an orifice in a'gas line and which is responsive to flow of gas into the line for removal from the orifice. The invention further comprises the apertures and process hereinafter described and claimed.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary vertical sectional view through a space heater applied to a building wall show-' ing the present invention installed in the gas line;

FIG. 2 is a vertical sectional view through the gas line and the plunger control apparatus;

FIG. 3 is a fragmentary enlarged view of the seating of the plunger rod heat in the fuel orifice; and

FIG. 4 is a fragmentary partly diagrammatic vertical sectional view of the present invention positioned on a heater mounted on an outside wall.

The present invention is embodied in a gaseous fuel line which supplies fuel to a gas fired burner 11 mounted within a combustion chamber 12 of a hot air heater 13. The heater 13 is of the sealed combustion chamber-type and is provided with a vent 14 on the outside wall 15 of a building. The back side of the heater 13 is mounted on the inside wall 16 of the building. The air for combustion enters the combustion chamber 12 through a duct 17 directly from outside the building. The air for combustion passes through a passageway 18 to the combustion chamber 12. The

flow of the combustion air is indicated on the arrows A in FIG. 4.

The products of combustion are discharged from the combustion chamber 12 through a duct 19 concentric with the air intake duct 17 and out through the vent 14. The flow of the products of combustion is indicated by the arrows B in FIG. 4.

The fuel line 10 leads to a thermostat actuated control or a manual on-off valve 20 which controls the flow of gaseous fuel through the line 10 to the burner 11. A pilot 21 is positioned adjacent to the burner 11 and ignites the burner 11 when the thermostat 20 opens the fuel supply valve incorporating therein. A fuel line 22 connects the pilot 21 to the valve 20.

A section of fuel line 10a connects the valve 20 to the burner 11 and in this fuel line 10a is positioned an orifice 23 and the orifice protective device 24 of the present invention.

The device 24 comprises a rod 25, which is designed to enter the orifice 23, mounted in the fuel line 10a. The rod is freely positioned in the line section 10a and is connected to a diaphragm 26 mounted within a housing 27 so as to divide the housing into two chambers 28 or 29. The rod passes through the chamber 28. The housing 27 is mounted in an elbow 30 by means of a threaded connecting pipe section 31 through which the rod 25 freely passes. The chamber 28 communicates with the fuel line 10a through the connecting pipe section 31. The diaphragm 26 is made of gas impermeable flexible leather or neoprene to separate the housing 27 into the two expansible sections 28 and 29. Stiffening members 32 and 33 are positioned on each side of the diaphragm 26 adjacent to the center, and the rod 25 is secured thereto by a nut 34.-

A spring 35 is positioned between the housing 27 and the stiffening member 33 in the chamber 29 and urges the rod 25 toward the orifice 23. A vent 36 communicates the chamber 29 with atmosphere through the housing 27.

In operation, when the valve 20 is closed so that the burner 11 is not operating, the rod 25 is seated in the orifice 23 because of the pressure of the spring 35. When the valve 20 opens, permitting gaseous fuel under pressure to enter the line 10a,.the fuel pressure acts against the diaphragm through the chamber 28, and because of the great area of the diaphragm, urges the diaphragm 26 against the pressure of the spring 35 so that the air trapped in the chamber 29 is control vented through the vent 36 to the atmosphere, permitting the chamber 29 to be contracted (while the chamber 28 is expanded) and thus the rod 25 moves out of the orifice 23. This permits flow of the pressurized fuel to the burner 11. When the gas valve in the valve 20 is turned off the pressure in the chamber 28 is removed from the diaphragm, and the spring pressure 35 seats the rod 25 in the orifice 23, thus sealing the came and preventing anything from entering the oriice.

This action also has the effect of cleaning the orifice 23 in the event that any contaminants from the fuel line 10 may have entered the orifice.

The rod 25 has a tapered nose 25a for better seating in the orifice 23 and for accommodating different sized orifices. I

What is claimed is:

- the burner and isfurther accessible to spiders and other insects which may enter the heating device and a valve in the fuel line for opening and closing the fuel line; the improvement comprising: blocking means shiftable between closed and open positions at the orifice, the blocking means generally closing the orifice when in its closed position to prevent the entry of spiders and fice and shifts toward the orifice when moving to its closed position and away from the orifice when moving to the open position.

4. The device according to claim 3 wherein the actuating means includes a housing defining a chamber in communication with the interior of the portion of the fuel line downstream from the valve, a diaphragm mounted on the housing and extended across the chamber so that the position of the diaphragm relative other insects into the orifice and permitting gas to flow from the orifice when in the open position; and actuating means connected to the blocking means for moving the blocking means between its open and closed positions, the actuating means being responsive to the pressure of the combustible gas in the fuel line downstream from the valve and moving the blocking means to its open position when the valve opens andto its closed position when the valve closes, whereby spiders and other insects will not enter the orifice and fuel line to clog the orifice when the valve is closed.

2. The device according to claim 1 wherein the ac tuating means includes a housing defining a chamber in communication with the interior of the fuel line downstream from the valve, a diaphragm mounted onto the chamber is responsive to the pressure of the combustible gas in the portion of the fuel line beyond the valve, the diaphragm being connected with the plunger for shifting the plunger axially as it moves relative to the chamber.

5. The device of claim 3 wherein the actuating means includes a housing mounted on the fuel line in alignment with the orifice, a flexible diaphragm separating the housing into tow expansible chambers, the plunger being mounted on and controlled by the diaphragm, and a spring urging the plunger means toward the orifice.

6. The device of claim 5 wherein the spring is mounted in one of the chambers between the diaphragm and the housing and a vent communicates said chamber to the atmosphere.

7. The device of claim 6 wherein the diaphragm is responsive to fuel pressure in the fuel line and opens said orifice when fuel is supplied to the burner through the line and the spring closes the orifice when the l ff lth ou hth f el line isinterru ted. Tfie d gvice of clairi: g whereinthe pliinger is an elongated rod havinga tapered nose for seating in the orifice when in the closed position.

' t I i 

1. In a heating device having a burner at which a combustible gas is burned, a fuel line connectable with a source of the combustible gas and terminating at an orifice which is directed into and located adjacent to the burner and is further accessible to spiders and other insects which may enter the heating device and a valve in the fuel line for opening and closing the fuel line; the improvement comprising: blocking means shiftable between closed and opEn positions at the orifice, the blocking means generally closing the orifice when in its closed position to prevent the entry of spiders and other insects into the orifice and permitting gas to flow from the orifice when in the open position; and actuating means connected to the blocking means for moving the blocking means between its open and closed positions, the actuating means being responsive to the pressure of the combustible gas in the fuel line downstream from the valve and moving the blocking means to its open position when the valve opens and to its closed position when the valve closes, whereby spiders and other insects will not enter the orifice and fuel line to clog the orifice when the valve is closed.
 2. The device according to claim 1 wherein the actuating means includes a housing defining a chamber in communication with the interior of the fuel line downstream from the valve, a diaphragm mounted on the housing and extended across the chamber so that the position of the diaphragm relative to the chamber is responsive to the pressure of the combustible gas in the fuel line downstream from the valve, the diaphragm being connected to the blocking means for moving the blocking means as it moves relative to the chamber.
 3. The device according to claim 1 wherein the blocking means is a plunger which aligns with the orifice and shifts toward the orifice when moving to its closed position and away from the orifice when moving to the open position.
 4. The device according to claim 3 wherein the actuating means includes a housing defining a chamber in communication with the interior of the portion of the fuel line downstream from the valve, a diaphragm mounted on the housing and extended across the chamber so that the position of the diaphragm relative to the chamber is responsive to the pressure of the combustible gas in the portion of the fuel line beyond the valve, the diaphragm being connected with the plunger for shifting the plunger axially as it moves relative to the chamber.
 5. The device of claim 3 wherein the actuating means includes a housing mounted on the fuel line in alignment with the orifice, a flexible diaphragm separating the housing into tow expansible chambers, the plunger being mounted on and controlled by the diaphragm, and a spring urging the plunger means toward the orifice.
 6. The device of claim 5 wherein the spring is mounted in one of the chambers between the diaphragm and the housing and a vent communicates said chamber to the atmosphere.
 7. The device of claim 6 wherein the diaphragm is responsive to fuel pressure in the fuel line and opens said orifice when fuel is supplied to the burner through the line and the spring closes the orifice when the supply of fuel through the fuel line is interrupted.
 8. The device of claim 3 wherein the plunger is an elongated rod having a tapered nose for seating in the orifice when in the closed position. 